Hi, I want to generate bit strings of length n and exactly m ones I came up with this algorithm but can't make it more efficient any Idea ? or am I doing optimization right ?

// cin >> number >> no;
// sample input 3 1 
// smaple output:
// 0 0 1
// 0 1 0
// 1 0 0

int number, nOnes, no;
int solution[10000];

void backtrack(int n) {
	if(n == number) {
		if(nOnes == no)
			print();
	} else {
		int candidates[] = {0, 1};
		for(int i = 0; i < 2; i++)
		{
			if(candidates[i] == 1) {
				nOnes += 1;
				if(nOnes > no){
					nOnes--;
					return;
				}
			}
			solution[n] = candidates[i];
			backtrack(n + 1);
			if(candidates[i])
				nOnes -= 1;
		}
	}
}